Integrated management of ash from industrial and domestic combustion : a new sustainable approach for reducing greenhouse gas emissions from energy conversion

This work supports, for the first time, the integrated management of waste materials arising from industrial processes (fly ash from municipal solid waste incineration and coal fly ash), agriculture (rice husk ash), and domestic activities (ash from wood biomass burning in domestic stoves). The main novelty of the paper is the reuse of wood pellet ash, an underestimated environmental problem, by the application of a new technology (COSMOS-RICE) that already involves the reuse of fly ashes from industrial and agricultural origins. The reaction mechanism involves carbonation: this occurs at room temperature and promotes permanent carbon dioxide sequestration. The obtained samples were characterized using XRD and TGA (coupled with mass spectroscopy). This allowed quantification of the mass loss attributed to different calcium carbonate phases. In particular, samples stabilized using wood pellet ash show a weight loss, attributed to the decomposition of carbonates greater than 20%. In view of these results, it is possible to conclude that there are several environmental benefits from wood pellet ash reuse in this way. In particular, using this technology, it is shown that for wood pellet biomass the carbon dioxide conversion can be considered negative

Investigation on the combined interactin of sulfate and acidic attack on concretes exposed to aggressive environments

Trabajo presentado al RILEM TC-251-SRT "Sulfate Resistance Testing" on External Sulfate Attack (TESA 2018), celebrado del 24 al 25 de mayo de 2018 en el Instituto de Ciencias de la Construcción Eduardo Torroja (IETCC-CSIC), Madrid, España.The study presented the results about the sulfuric acid corrosion, at very low pH, of a concrete containing blast furnace slag and fly-ash as SCM. Since no standard method are present regarding the acid corrosion, the comparison of the results between different laboratories is strongly related to the experimental conditions. In this research two methods were compared based on the complete concrete immersion in a sulfuric acid solution with different approaches to keep the pH 2 constant. The evolution of damage was followed by the loss of mass (kg/m2); moreover, the microstructure was observed by electron-scanning microscopy and the elastic modulus was performed as non-destructive test (NDT). The rate of degradation after 35 days of exposure, according the loss of mass due to the calcium dissolution of cement paste, is comparable between the two methods. The influence on the experimental parameters and the relation with the combined sulphate and acidic attack is discussed.This work was financially supported by the European Union’s H2020 grant agreement ID 685445 under the LORCENIS Project (https://www.sintef.no/projectweb/lorcenis/)

Durability and chromatic behavior in cement pastes containingceramic industry milling and glazing by-products

The decay in mortar and concrete induced by extremely aggressive agents is nor-mally the result of the agent‐binder reaction. Cement composition and characteris-tics therefore determine the durability of the mortars and concretes of which theyform part. The existing legislation envisages the use of different types of additionsin cement, which have a direct effect on the durability of elements in buildingsand civil works. This study addressed the inclusion of ceramic industry millingand glazing sludge as an active addition in cement. The reuse of this industrialwaste is consistent with environmental policies that seek to reduce or eliminatespoil heaps by recycling industrial waste and byproducts as raw materials, inkeeping with circular economy principles. The research conducted makes an inno-vative contribution to the valorization of this waste, and highlights the resistanceof blended cement pastes to chemical agents, further to the Koch‐Steineggermethod. Water‐induced decay in freeze/thaw situations was also studied. The pro-cesses involved were identified by analyzing the mineralogical variations detectedwith X‐ray diffraction, the morphological alterations observed with scanning elec-tron microscopy and the mercury porosimetric findings on pore size distribution.The suitability of these binders for aesthetically demanding applications was alsoexplored by measuring the color in pastes exposed to aggressive chemical agents.For the first time, a correlation was established between color parameters and theformation of the reaction products generated during chemical attackThis research was funded by several Spanish Ministries (Projects BIA 2013‐48876‐C3‐1‐R, BIA 2013‐48876‐C3‐2‐R, BIA2016‐76643‐C3‐1‐R). Supply of the ceramic sludge used in this study by ADICEM Valorización S.L. is gratefully acknowledged.Peer reviewe